Which of the following is consistent with a spontaneous process in the forward direction? A) ∆Suniv >0, ∆G<0, T∆Suniv >0.
B) ∆Suniv <0, ∆G>0, T∆Suniv <0.
C) ∆Suniv >0, ∆G<0, T∆Suniv <0.
D) ∆Suniv <0, ∆G<0, T∆Suniv <0.
E) ∆Suniv >0, ∆G>0, T∆Suniv >0.

A) ∆Suniv >0, ∆G<0, T∆Suniv >0.

Explanation:

The connection between entropy and the spontaneity of a reaction is expressed by the second law of thermodynamics: The entropy of the universe increases in a spontaneous process and remains unchanged in an equilibrium process.

Mathematically, we can express the second law of thermodynamics as follows:

For a spontaneous process: ΔSuniv = ΔSsys + ΔSsurr > 0

Therefore, the second law of thermodynamics tells us that a spontaneous reaction increases the entropy of the universe; that is, ΔSuniv > 0.

If we want spontaneity expressed only in terms  of the properties of the system (ΔHsys and ΔSsys), we use the following equation:

-TΔSuniv = ΔHsys - TΔSsys < 0

That means that T∆Suniv >0.

This equation says that for a process carried out at constant pressure and temperature  T, if the changes in enthalpy and entropy of the system are such that ΔHsys - TΔSsys  is less than zero, the process must be spontaneous.

Finally, if the change in free energy is less than zero (ΔG<0), the reaction is spontaneous in the forward direction.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.